Reel mower with adjustable bedknife having constant longitudinal location relative to reel

ABSTRACT

A walk reel mower includes a pair of inclined rigid links for mounting the reel cutting unit to the reel mower frame for rolling about a longitudinal axis, and a pair of vertical support arms for mounting the reel cutting unit to the reel mower frame for pitching about a transverse axis. An integrated gearbox houses both the traction and reel drives, including the differential that is part of the traction drive, as well as a parking brake. A flexible drive shaft powers the cutting reel from the gearbox and is made from materials that do not require petroleum based lubricants to avoid the possibility of damage to the turf or grass. A single control handle located on the handle of the mower actuates both the reel and traction drives. The reel cutting unit includes a back plate which has a portion formed as a hollow beam for strength. The reel cutting unit also has a pivot axis for the bedknife allowing adjustment of the bedknife relative to the cutting reel without changing the longitudinal location of the front edge of the bedknife to ensure consistent cutting of the cutting unit. Finally, an improved mounting for the grass basket used on the cutting unit is disclosed which mounting avoids inadvertent disengagement of the grass basket from the cutting unit.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a division of application Ser. No. 10/620,328, filedJul. 15, 2003, now U.S. Pat. No. 7,191,584 which is a division ofapplication Ser. No. 09/892,194, filed Jun. 26, 2001, U.S. Pat. No.6,622,464, which claims the benefit of provisional application No.60/214,133 filed Jun. 26, 2000.

TECHNICAL FIELD

This invention relates to a walk reel mower having a reel cutting unitthat “floats” relative to the reel mower frame to allow the reel cuttingunit to conform to the ground contours to avoid scalping and/or scuffingof the turf being cut. In addition, this invention relates to a gearboxthat integrates the traction and reel drives of the reel mower, to aself-lubricating drive shaft that transfers drive to the cutting reel,to a single control handle for operating both the traction and reeldrives, to an improved mounting on the reel mower frame for supportingthe grass collecting basket, to an improved pivotal mounting for thebedknife, and to an improved back plate construction for the reelcutting unit.

BACKGROUND OF THE INVENTION

Walk reel mowers are known for precision cutting of grass and the like,such as the grass found on golf greens. Such reel mowers typically havea frame which carries a reel cutting unit. A handle assembly extendsupwardly and rearwardly from the frame to allow an operator who walksbehind the mower to guide and operate the mower. The handle assemblyincludes various controls for allowing the operator to selectivelyengage and disengage the traction drive of the mower as well as the reelcutting unit.

Prior art walk reel mowers are known in which the reel cutting unit iscarried rigidly on the frame, like that shown in U.S. Pat. No. 5,477,666to Cotton or U.S. Pat. No. 4,481,757 to Tsuchiya. Such a cutting unitdoes not pitch, roll or yaw relative to the frame to adapt itself to thecontours of the ground. When this mower cuts grass on an undulatingsurface, it is quite possible to scalp or scuff the grass. For example,the grass might be cut too closely on top of a high spot and not closelyenough in a low spot. This is undesirable.

Other reel mowers, such as that shown in U.S. Pat. No. 2,972,218,disclose walk reel mowers having a “full floating cutting unit” that canmove in three degrees of freedom relative to the mower frame. This isdone by making the cutting unit self-supporting on its own front andrear rollers. The cutting unit is then suspended from the mower frame bya set of chains that are normally slack when the cutting unit is inengagement with the ground. The slack chains allow the cutting unit tomove relative to the mower frame to better follow the contours of theground to minimize instances of scalping and/or scuffing and to helpprovide a more consistent height of cut.

While the ground contour following characteristics of a reel mower arenot possessed by a reel mower with a cutting unit that is rigid with theframe, the use of chains to support the cutting unit providesdisadvantages of its own. When the operator pushes down on the handleassembly to raise the front end of the reel mower, the cutting unit doesnot immediately lift up off the ground. The chains first have to tightenbefore the cutting unit lifts up off the ground. Thus, when pushing downon the handle to lift the cutting unit off the ground, the operatorfirst feels a smooth motion while the chains tighten and then feels ajerk or discontinuity when the operator suddenly has to push down harderto get the cutting unit to come up.

The jerk or discontinuity felt by the operator in the handle as theoperator pushes down on the handle to raise the cutting unit is adisadvantage. Most operators prefer cutting units in which one can pushdown on the handle to raise the cutting unit and this can be done in asmooth motion with the cutting unit raising immediately. This is simplynot possible with cutting units suspended by chains that must betightened before the cutting unit rises.

U.S. Pat. No. 2,329,952 to Speiser discloses a walk reel mower in whicha reel cutting unit is mounted on the rear of the mower frame. However,the cutting unit has a floating capability in that the cutting unit canpitch and roll relative to the frame by virtue of transverse andlongitudinal pivots between the cutting unit and the mower frame. Whilethis provides a ground contour following ability without using slackchains to support the cutting unit, pushing down on the handle assemblywill not lift the cutting unit off the ground. Thus, the mower shown inthe Speiser patent is much more difficult to maneuver than the reelmowers described earlier.

In addition, the cutting unit shown in the Speiser patent is not itselftotally self-supporting on the ground, but relies on the traction wheelsof the mower frame in conjunction with a roller on the cutting unit forproper ground engaging support. As a result, the fore-and-aft wheelbaseof the mower is relatively large. This decreases how effectively thecutting unit will pitch when encountering transverse bumps orundulations in the ground, i.e. bumps or undulations that areperpendicular to the forward direction of motion. If the bump is smallenough, the traction wheels may clear the bump before the cuttingreel/bedknife interface reaches the high spot of the bump, thus stillresulting in scalping.

Another problem with prior art walk reel mowers is the nature of thedrives or transmissions used to power the traction drive and the cuttingreel. Often, separate drives housed in separate gearboxes are used, onegearbox powering the traction drive and the other gearbox powering thecutting reel. The use of two gearboxes increases expense as well asrequiring sufficient space on the mower frame for housing bothgearboxes. In addition, the use of two gearboxes gives the mower acluttered appearance.

Moreover, in many prior art walk reel mowers, a differential is neededto allow the left and right traction wheels, or the left and righttraction drum halves, to rotate at different speeds when turning. Inmany prior art mowers, particularly those having a traction drum formedfrom traction drum halves including a left traction drum half and aright traction drum half, the differential was not carried in the speedreducing gearbox, but was instead built into the interior of thetraction drum. In this location, it was difficult to keep thedifferential sealed and lubricated, and repair or replacement of thedifferential was also difficult. Moreover, any leakage of the lubricantfrom the differential out of the traction drum is problematic as such alubricant can easily kill or mar the grass or turf being cut by themower.

Some attempts are disclosed in the art to integrate the drives for thecutting reel and the traction drive into a single gearbox. One suchattempt is shown in U.S. Pat. No. 1,709,791 to Jerram, in which thespeed reducing gear drives used to power the traction drum and thecutting reel are housed in a common gearbox or gearcase that is builtinto one of the side plates of the reel mower frame. The clutches usedto initiate operation of the drives for the traction drum and thecutting reel are also both housed in this common gearbox. Thus, thismower has only a single gearbox for enclosing both the traction andcutting reel drives, thus having a less cluttered appearance than mowersusing multiple gearboxes.

Despite the attempt at simplification shown in the Jerram patent,various deficiencies are still present. For example, the differentialfor the traction drum is still housed within the interior of thetraction drum. This gives rise to the lubricating and lubricant leakageproblems discussed above. In addition, the overall drive anddifferential systems disclosed in Jerram involve the use of a largenumber of components, which leads again to increased cost.

In reel mowers in which the cutting unit floats to follow the contoursof the ground, the drive to the cutting reel has to flex, bend andaxially extend and contract to accommodate the floating motion of thecutting unit. In some mowers, such as that shown in the Speiser patentreferred to above, this is accomplished using a flexible drive beltextending from one sprocket or pulley on the mower frame to anothersprocket or pulley on the cutting unit. It is a problem with such adrive in keeping the belt taut as the cutting unit and mower frame moverelative to one another. In addition, flexing or twisting of the drivebelt is quite hard on the belt leading to relatively short belt life.

Other non belt type drives are known for the cutting reel. For example,flexible shafts are known for accomplishing this drive with one suchshaft shown in U.S. Pat. No. 2,191,135 to Roth. This shaft comprises twouniversal joints at either end connected by relatively slidable shaftsections. The shaft sections have mating, non-circular cross-sectionalconfigurations to allow torque to be transmitted while the shaftsections slide in and out relative to one another. See FIGS. 7 and 9 ofRoth.

While flexible shafts are known for powering floating cutting units,they must be lubricated to function quietly and properly and to haveadequate life. Again, having to lubricate a flexible drive shaft to thecutting reel is a problem because such a flexible drive shaft isgenerally exposed and located above the cutting reel. Thus, thelubricant for the drive shaft or the universal joints at either end canleak and drop down onto the grass or turf, thus damaging the grass orturf. As in the case with leakage of the lubricant from a drum carrieddifferential, this is not desirable.

In many prior art walk reel mowers, the controls used to place thetraction drive and cutting reel in operation are separate from oneanother. In many cases, the control for operating the cutting reel isnot carried on the handle assembly, but is located down on the mowerframe adjacent the cutting reel itself. The other control for operatingthe traction drive is located up on the handle assembly. Such a dualcontrol system, with the cutting reel control being down on the mowerframe while the traction drive control is on the handle, is shown inU.S. Pat. No. 1,947,117 to Stegeman.

This prior art control system is disadvantageous as it is relativelycumbersome to start and stop the cutting reel. For example, to start andstop operation of the cutting reel, the operator has to walk from behindthe handle assembly to a position around in front of the handle assemblyin order to reach the control that starts or stops the drive to thecutting reel. After the operator manually actuates this control, theoperator must then walk back behind the handle assembly to continueoperation of the mower. This back and forth walking motion is obviouslyinconvenient and tiring to do. As a result, the operator tends to leavethe cutting reel in operation even at times when the cutting reel shouldotherwise be shut off.

In some prior art mowers, such as that shown in the Speiser patentreferred to above, the controls for the traction drive and cutting reelare both carried on the handle assembly. At least in this device, thecontrols can both be reached and operated by the operator without havingto walk around in front of the handle assembly. However, two separatecontrols are still provided, each with its own handle and controllinkage. As such, the controls can be somewhat confusing to use as theoperator must remember which control operates which item. Moreover, theuse of separate controls again unduly clutters the handle assembly.

In walk reel mowers, it is common to collect grass clippings in a grasscollection basket mounted to the mower frame so that the basket ispositioned in front of the cutting unit. Sometimes, when the operatorlifts up on the handle assembly of the mower when maneuvering the mower,it is possible for the grass basket to become disengaged from the mower.This requires that the operator walk around and reattach the basket tothe frame. If the basket is partially filled with grass clippings, thiscan be difficult to do. Even if it can be done, it is inconvenient forthe operator to have to reattach the grass basket.

Finally, in many reel mowers, whether they be walk reel mowers or ridingreel mowers, it is common to pivot the bedknife towards the cutting reelto compensate for wear in the cutting reel. This has the effect oflongitudinally moving the front edge of the bedknife from the positionit occupies when the cutting reel is not worn. For example, in a cuttingreel with a relatively unworn reel, the front edge of the bedknife mighttypically be behind the center of the cutting reel by a certain amount.When the reel wears and the bedknife is pivoted up to maintain properclearance to the cutting reel, this behind the center distance willchange.

The Applicants have found that this change in the behind the centerdistance of the bedknife affects how aggressively the cutting reel cuts.Thus, after the reel becomes worn and the bedknife is adjusted in themanner just described, the cutting unit will cut differently than whenthe reel was new and the bedknife had not been adjusted from its initialorientation. This change in the quality of the cutting is not desirable.It would be best for the cutting unit to cut approximately the sameregardless of how worn the cutting reel has become and whether or notthe bedknife has been adjusted to compensate for this wear.

SUMMARY OF THE INVENTION

It is one aspect of this invention to provide a walk reel mower thatincludes a cutting unit that can at least partially float to follow thecontours of the ground. This aspect is provided, inter alia, by a walkreel mower which comprises a reel mower frame on which a power source iscarried. An upwardly extending handle assembly is connected at its lowerend to the reel mower frame, the handle assembly including a portionwhich the operator can grip to guide the reel mower frame while theoperator walks behind the reel mower frame. A traction drive is providedfor propelling the reel mower frame across the ground, the tractiondrive being powered by the power source. A reel cutting unit is carriedon the front of the reel mower frame. The reel cutting unit has a reelcutting unit frame which carries a helically bladed cutting reel whichis rotatable about a substantially horizontal, transverse axis, abedknife which cooperates with the cutting reel such the rotatablecutting reel sweeps standing grass against the bedknife to cut thegrass, and front and rear ground engaging wheel or roller supports forallowing the reel cutting unit to be self supporting and to move overthe ground. A suspension system comprising relatively rigid links isprovided for pivotally connecting the reel cutting unit frame to thereel mower frame such that the reel cutting unit can roll about asubstantially horizontal, longitudinal axis.

Another aspect of this invention relates to a walk reel mower whichcomprises a reel mower frame on which a power source is carried. Anupwardly extending handle assembly is connected at its lower end to thereel mower frame, the handle assembly including a portion which theoperator can grip to guide the reel mower frame while the operator walksbehind the reel mower frame. A traction drive is provided for propellingthe reel mower frame across the ground, the traction drive being poweredby the power source. A reel cutting unit is carried on the reel mowerframe. The reel cutting unit has a cutting reel which is rotatable abouta substantially horizontal, transverse axis which reel cooperates with abedknife to cut grass. A reel drive is provided for powering the cuttingreel, the reel drive being powered by the power source. A single gearboxhouses the traction drive and the reel drive.

Yet another aspect of this invention relates to the traction drive for awalk reel mower having ground engaging, traction drive elements forpropelling the walk reel mower over the ground. The traction drivecomprises a planetary gear carrier having a plurality of planetary gearsrotating around a sun gear with the planetary gears and sun gear beingcontinuously driven by a power source on the walk reel mower when thepower source is operating. A traction drive clutch drum engages theplanetary gear carrier and rotates therewith. A traction drive gear isoperatively coupled to the planetary gears, the traction drive gearfurther being operatively coupled to the ground engaging tractionelements. A selectively operable brake is provided for engaging thetraction drive clutch drum to stop movement of the planetary gearcarrier such that the continued rotation of the planetary gears willthen rotate the traction drive gear to power the ground engagingtraction drive elements.

Another aspect of this invention relates to a drive shaft fortransferring rotational torque to a reel cutting unit of a reel mower.The drive shaft has an expandable length and is flexible between eachend thereof to accommodate movement of the reel cutting unit relative tothe reel mower. The drive shaft is self-lubricating without usingpetroleum based lubricants.

Yet another aspect of this invention relates to a walk reel mower whichcomprises a reel mower frame on which a power source is carried. Anupwardly extending handle assembly is connected at its lower end to thereel mower frame. The handle assembly includes a portion which theoperator can grip to guide the reel mower frame while the operator walksbehind the reel mower frame. A traction drive is provided for propellingthe reel mower frame across the ground, the traction drive being poweredby the power source. A reel cutting unit is carried on the reel mowerframe, the reel cutting unit having a cutting reel which is rotatableabout a substantially horizontal, transverse axis which reel cooperateswith a bedknife to cut grass. A reel drive is provided for powering thecutting reel, the reel drive being powered by the power source. Finally,a single control handle is carried on the handle assembly forselectively controlling the operation of both the traction drive and thereel drive.

Another aspect of this invention relates to a walk reel mower whichcomprises a reel mower frame on which a power source is carried. Anupwardly extending handle assembly is connected at its lower end to thereel mower frame, the handle assembly including a portion which theoperator can grip to guide the reel mower frame while the operator walksbehind the reel mower frame. A reel cutting unit is carried on the frontof the reel mower frame. The reel cutting unit has a reel cutting unitframe which carries a helically bladed cutting reel which is rotatableabout a substantially horizontal, transverse axis, and a bedknife whichcooperates with the cutting reel such the rotatable cutting reel sweepsstanding grass against the bedknife to cut the grass. A grass basket isattached to the reel cutting unit frame ahead of the cutting reel andthe bedknife. The grass basket is attached to the reel cutting unitframe by pins on the basket received in sockets on the reel cutting unitframe. The pins and sockets are configured relative to one another sothat the grass basket will not be disengaged if the operator lifts up onthe handle assembly.

Yet another aspect of this invention relates to a reel cutting unit fora reel mower which comprises a reel cutting unit frame comprising spacedside plates connected to an arcuate back plate. A helically bladedcutting reel is rotatably journalled between the side plates andpositioned in front of the back plate. A bedknife extends between theside plates along the length of cutting reel for cooperating with thecutting reel to cut grass. The bedknife is pivotally adjustable relativeto the side plates to compensate for wear in the cutting reel. The pivotaxis of the bedknife is chosen such that the front edge of the bedknifestays in approximately the same longitudinal location relative to thecutting reel as the front edge of the bedknife rises upwardly tocompensate for wear in the cutting reel.

A final aspect of this invention relates to a reel cutting unit for areel mower which comprises a reel cutting unit frame comprising spacedside plates connected to an arcuate back plate. A helically bladedcutting reel is rotatably journalled between the side plates andpositioned in front of the back plate. A bedknife extends between theside plates along the length of cutting reel for cooperating with thecutting reel to cut grass. At least portion of the back plate has aclosed tubular cross-sectional configuration. This aspect of thisinvention also relates to the back plate per se.

BRIEF DESCRIPTION OF THE DRAWINGS

This invention will be described hereafter in the Detailed Description,taken in conjunction with the following drawings, in which likereference numerals refer to like elements or parts throughout.

FIG. 1 is a perspective view of a first embodiment of a walk reel moweraccording to this invention, with the grass collecting basket beingshown on the reel cutting unit in this view but with such a basket notbeing shown in any of FIGS. 2-9 for the purpose of clarity;

FIG. 2 is a perspective view of a portion of the walk reel mower shownin FIG. 1, particularly illustrating the reel cutting unit and the pairof inclined rigid links that mount the cutting unit carrier frame forrolling motion relative to the reel mower frame;

FIG. 3 is a front elevational view of a portion of the walk reel mowershown in FIG. 1, particularly illustrating the reel cutting unit and thefocal point F of the rigid links that mount the cutting unit carrierframe to the reel mower frame;

FIG. 4 is a right side elevational view of a portion of the walk reelmower shown in FIG. 1;

FIG. 5 is a left side elevational view of a portion of the walk reelmower shown in FIG. 1;

FIG. 6 is a top plan view of a portion of the walk reel mower shown inFIG. 1, particularly illustrating the self-lubricating drive shaft thattransfers drive from the gearbox located on the reel mower frame to thecutting reel;

FIG. 7 is a diagrammatic side elevational view of the walk reel mowershown in FIG. 1, particularly illustrating the pitching motion of thereel cutting unit about a substantially horizontal transverse axis;

FIGS. 8 and 9 are diagrammatic front elevational views of the walk reelmower shown in FIG. 1, particularly illustrating the rolling motion ofthe reel cutting unit about a substantially horizontal longitudinalaxis;

FIG. 10 is a perspective of an integrated gearbox that provides both thetraction and reel drives for the walk reel mower shown in FIGS. 1 and14;

FIG. 11 is an exploded perspective view of the gearbox shown in FIG. 10;

FIG. 12 is an enlarged perspective view of the gearbox shown in FIG. 10,but with the side covers of the gearbox having been removed toillustrate the interior of the gearbox and particularly to illustratethe traction drive clutch drum, the drive gear interconnecting the ringgear and the input gear of the differential, the traction drive bandbrake surrounding the traction drive clutch drum, and the output gear onthe cutting reel drive shaft;

FIG. 13 is an enlarged side elevational view of the gearbox shown inFIG. 10, with FIG. 13 being similar to FIG. 12 in that the side coversof the gearbox have been removed to illustrate the interior of thegearbox to thereby illustrate the same components as are shown in FIG.12;

FIG. 14 a perspective view of a second embodiment of a walk reel moweraccording to this invention, with the grass collecting basket beingshown detached from the reel cutting unit in this view and sitting onthe ground in advance of the reel cutting unit, this embodiment of thewalk reel mower having a single, integrated control handle forcontrolling both the reel and traction drives and another control handlefor actuating the parking brake;

FIG. 15 is a perspective view of the single, integrated control handleshown in FIG. 14 for controlling both the reel and traction drives;

FIG. 16 is an exploded perspective view of the single, integratedcontrol handle shown in FIG. 14 for controlling both the reel andtraction drives;

FIG. 17 is a perspective view of a portion of the walk reel mower shownin FIG. 14, particularly illustrating the mounting on the reel mowerframe for supporting the grass collecting basket;

FIG. 18 is a top plan view of that portion of the walk reel mower shownin FIG. 17;

FIG. 19 is a side elevational view of that portion of the walk reelmower shown in FIG. 17;

FIG. 20 is a side elevational view of the reel cutting unit used in thewalk reel mower of this invention, particularly illustrating the pivotalmount for the bedknife; and

FIG. 21 is a side elevational view of the reel cutting unit used in thereel mower of this invention with one of the side plates removed to showthe cross-sectional shape of the back plate of the reel cutting unitframe.

DETAILED DESCRIPTION

This invention relates to a walk reel mower 2 having a reel cutting unitfor cutting grass. The term “walk reel mower” is used in thisapplication to refer to a walk reel mower 2 in which the operator walksbehind walk reel mower 2 as walk reel mower 2 is operated. The operatoris not supported or carried by walk reel mower 2 as would be the casewith a riding reel mower. More particularly, walk reel mower 2 is suitedfor mowing grass at low heights of cut where precision cutting isrequired, such as on the greens of a golf course. However, the variousaspects of the invention disclosed herein are not limited for use on awalk reel mower for mowing only golf greens, but can be used on walkreel mowers for mowing other turf areas as well.

The Overall Walk Reel Mower

FIG. 1 provides an overall view of one embodiment of a walk reel mower 2according to this invention. Walk reel mower 2 includes a frame 4 onwhich a power source 6, such as an internal combustion engine, iscarried. Other power sources 6 could be used in place of the internalcombustion engine or in addition to the internal combustion engine. Forexample, the internal combustion engine could be replaced by an electricmotor driven by a rechargeable battery pack carried on reel mower frame4 of walk reel mower 2. Alternatively, a hybrid internal combustionengine/battery pack power system could be used for supplying electricalpower to an electric motor. Thus, the nature of power source 6 is notimportant to the various aspects of the invention disclosed herein aslong as such a power source 6 has a rotating output shaft from whichpower can be drawn.

Walk reel mower 2 includes a U-shaped, upwardly extending handleassembly 8 that is connected at its lower end to reel mower frame 4 ofwalk reel mower 2. Handle assembly 8 includes an upper cross bar 10which the operator can grip to guide walk reel mower 2 during operationthereof. Various operational controls are provided on handle assembly 8for allowing the operator to control the operation of the traction driveand cutting reel drive of walk reel mower 2. The embodiment of FIG. 1discloses a first set of such controls while the embodiment of FIG. 14discloses a second set of such controls.

Walk reel mower 2 is propelled across the ground by a traction driveincluding a split traction drum 12 rotatably carried at the rear of reelmower frame 4. Traction drum 12 is split, as is conventional, into twohalves, a left half 12 l and a right half 12 r. Traction drum halves 12l and 12 r are independently driven by a differential to allow adifference in rotational speed between traction drum halves 12 l and 12r when walk reel mower 2 is turning.

The rotational shaft 14 l and 14 r for each traction drum half 12 l or12 r is extended outwardly to mount a transport wheel 16 on each side ofwalk reel mower 2. Transport wheels 16 are used only when walk reelmower 2 is being driven from one site to another. When walk reel mower 2is being used to cut grass, transport wheels 16 are removed. Walk reelmower 2 is then supported and driven solely by traction drum 12.

If desired, traction drum halves 12 l and 12 r could be replaced byseparate left and right drive wheels engaging the ground in the mannerof transport wheels 16. In this case, such drive wheels would not beremoved and would support walk reel mower 2 for movement over the groundat all times.

A reel cutting unit 18 of generally conventional design is carried onthe front of reel mower frame 4. Reel cutting unit 18 includes a reelcutting unit frame 19 comprising spaced side plates 20 connected to anarcuate back plate (not shown in FIG. 2). A helically bladed cuttingreel 22 is rotatably journalled between side plates 20 and is positionedin front of the back plate. As cutting reel 22 rotates, the reel bladessweep standing grass against a sharpened bedknife 24 to thereby severthe grass. Bedknife 24 extends between side plates 20 along the lengthof cutting reel 22. Bedknife 24 is shown in FIGS. 4, 5 and 19.

Reel cutting unit 18 is self supporting for rolling over the ground orturf by front and rear rollers 26 and 28 extending between side plates20. The height of cut can be adjusted in any conventional manner. Forexample, front roller 26 can be moved up and down relative to sideplates 20 by a threaded height adjusting mechanism 30 carried on eachside plate 20. In addition, bedknife 24 can be adjusted relative tocutting reel 22 by bedknife adjusters 32 carried on the top of reelcutting unit 18. Such bedknife adjusters 32 are designed to maintain aconstant spring force on bedknife 24 throughout the life of cutting reel22.

The Reel Cutting Unit Suspension System

One aspect of this invention relates to how reel cutting unit 18 issupported on reel mower frame 4. Reel cutting unit 18 is allowed tofloat or move relative to reel mower frame 4 about two axes. First, reelcutting unit 18 can roll about a longitudinal axis, i.e. a fore-and-afthorizontal axis x. See FIG. 8. Second, reel cutting unit 18 can pitchabout a transverse axis, i.e. a side-to-side horizontal axis y which iscoaxial with the axis of cutting reel 22. See FIG. 7. Motion of reelcutting unit 18 about the axes x and y allow reel cutting unit 18 tobetter conform to the contours of the ground being cut to avoidscalping. This is particularly important when cutting golf greens,especially those found on newer golf courses in which the greens oftenhave pronounced undulations.

Reel cutting unit 18 is supported in the above described manner by agenerally U-shaped cutting unit carrier frame 34. Cutting unit carrierframe 34 includes a transverse cross member 36 having downwardlyextending, vertical support arms 38 at either end thereof. Each verticalsupport arm 38 passes downwardly through a slot in a top wall of reelcutting unit 18 to lie adjacent one side plate 20. The lower end of eachvertical arm 38 includes an inwardly protruding circular hub 40 whichrotatably engages or journals the shaft of cutting reel 22. Thus, duringoperation of walk reel mower 2, reel cutting unit 18 can pivot or rockback and forth in the direction of the arrows A in FIG. 7 by pivoting orrocking on the inwardly protruding hubs 40 of vertical support arms 38.

Cutting unit carrier frame 34 is further suspended from reel mower frame4 by at least one pair of inclined rigid links 42. Referring to FIG. 3,the upper end of each link 42 is pivotally secured to reel mower frame 4while the lower end of each link 42 is pivotally secured to cross member36 of cutting unit carrier frame 34. Each link 42 is located offset fromthe longitudinal centerline of reel cutting unit 18 so that links 42 areon opposite sides of the centerline, i.e. one link 42 is offset to theleft of the centerline while the other link 42 is offset to the right ofthe centerline. Links 42 are further inclined inwardly relative to oneanother and relative to a vertical line passing through the upper end ofeach link 42. In other words, the lower end of each link 42 is closer tothe longitudinal centerline of reel cutting unit 18 than is the upperend of each link 42.

Accordingly, lines drawn through links 42 will be inclined towards eachother and will eventually intersect at a focal point F shown in FIG. 3.Focal point F lies along the longitudinal axis x about which the cuttingunit rolls. In addition, focal point F at which the lines of action oflinks 42 intersect is selected to be at the center of bedknife 24, atleast when reel cutting unit 18 is sitting on flat and level ground.This is achieved by controlling the placement and angle of inclinationof links 42.

Links 42 are provided in a first pair of links 42 which attach to thefront of cross member 36, and in a duplicate second pair of links 42′which attach to the rear of cross member 36. See FIG. 6. Links 42 in thefirst pair of links are contained in a first transverse plane whilelinks 42′ in the second pair of links are contained in a secondtransverse plane that is offset from the first plane by the thickness ofcross member 36. Using two pairs of duplicate links 42, 42′ as disclosedherein suspends reel cutting unit 18 in an efficient and durable mannerwithout putting undue stress on any single pair of links.

While a suspension system for reel cutting unit 18 has been shown whichcomprises a duplicate pair of inclined, rigid links 42, it would bepossible to use only a single pair of links 42. In addition, fourpivotal links could also be used in an arrangement where each link waslocated adjacent one corner of reel cutting unit 18 and extendedupwardly therefrom to some overlying portion of reel mower frame 4. Eachlink would again be inclined inwardly to point towards a common focalpoint F located at the center of bedknife 24.

Referring now to FIGS. 7-9, the various permitted motions of reelcutting unit 18 during operation of walk reel mower 2 are illustrated.FIG. 7 shows the pitching motion of reel cutting unit 18 about thetransverse axis y, the phantom line positions illustrating the pitchingmotion. FIGS. 8 and 9 illustrate the rolling motion of reel cutting unit18 about the longitudinal axis x. The rolling motion is depicted by thearrows B in FIGS. 8 and 9. FIG. 8 illustrates reel cutting unit 18having rolled to one side while FIG. 9 illustrates reel cutting unit 18having rolled to the opposite side. Note the pivoting of the pair oftransverse links 42 which permits this rolling motion.

The Applicants' have found the use of at least a pair of inwardly,inclined rigid links 42 to support reel cutting unit 18 for rollingmotion to be particularly advantageous. Because links 42 point towards afocal point F located at the center of bedknife 24 when reel cuttingunit 18 is level, it is as if the entire reel cutting unit 18 is rollingabout the longitudinal axis x containing focal point F. Accordingly,scalping or scuffing of the turf is minimized as reel cutting unit 18rolls.

It is preferred that the focal point F for the rigid suspension links 42be located at the center of bedknife 24. However, other focal points Fcould also be used, such as a focal point F located at the surface of orslightly below the surface of the ground. It is desirable that the focalpoint F be low relative to reel cutting unit 18 and to the ground tominimize turf scalping or scuffing. Using a focal point F at the centerof bedknife 24 accomplishes both keeping the focal point low as well askeeping the focal point F longitudinally centered relative to reelcutting unit 18. However, other focal points F could be used althoughsuch focal points are desirably kept relatively low with respect to reelcutting unit 18.

One advantage of the suspension system described above is that all“floating movement” of reel cutting unit 18 is achieved by a rigidsuspension system, i.e. the rigid links 42 as well as the rigid cuttingunit carrier frame 34. Thus, when the operator wishes to tip reelcutting unit 18 up off the ground by pushing downwardly on handleassembly 8 to raise the front end of walk reel mower 2, reel cuttingunit 18 will rise immediately without having to take up any slack inflexible chains or the like, as is required in more traditional mowersthat often support the reel cutting unit with chains. Thus, theunevenness and jerkiness encountered in prior art walk reel mowersduring this operation, i.e. relatively easy lifting until the chainstighten and then the need for a greatly increased force to raise reelcutting unit 18, is avoided. Thus, walk reel mower 2 of this inventionhas the solid feel and handling of a walk reel mower in which the entirereel cutting unit 18 is rigidly carried on walk reel mower 2, but yetprovides much of the floating motion permitted by a chain typesuspension system for reel cutting unit 18.

The Integrated Gearbox Providing Traction Drive, Reel Drive, and ParkingBrake

Another aspect of this invention relates to a greatly simplified gearbox44 for providing a traction drive 46 for powering traction drum 12 aswell as a reel drive 48 for powering cutting reel 22. The clutches usedto initiate traction drive 46 and reel drive 48 are all contained withingearbox 44. A differential 54 and much of the speed reduction gearingrequired for traction drive 46 are contained in gearbox 44 as well.Finally, gearbox 44 includes a parking brake 56. The clutches requiredto actuate traction drive 46 and parking brake 56 are simple,tightenable band brakes.

Both of the embodiments shown in FIGS. 1 and 14 use this gearbox 44 withgearbox 44 being generally identical in both embodiments. Gearbox 44shown in FIG. 1 includes a vent 45 which is not present in gearbox 44shown in FIG. 14. Other than for this difference, gearboxes 44 shown inFIGS. 1 and 14 are identical.

FIG. 10 is a perspective view of the improved gearbox 44 of thisinvention with gearbox 44 having been removed from walk reel mower 2.FIG. 11 is an exploded perspective view of the improved gearbox 44 ofthis invention. Gearbox 44 will be described primarily, though notexclusively, with reference to these figures, and mostly with referenceto FIG. 11.

Referring now to FIG. 11, gearbox 44 includes a traction drive shaft 58extending across gearbox 44. A sun gear 60 is carried on traction driveshaft 58. In addition, a planetary gear carrier 62 having a plurality ofplanetary gears 64 (only one of which is shown in FIG. 11) is rotatablyjournalled on traction drive shaft 58 by needle bearings 66. There arethree planetary gears 64 and each planetary gear 64 is rotatably carriedon planetary gear carrier 62 by a pin or dowel 68.

Traction drive shaft 58 is driven from the output shaft of power source6 by a power source gear (not shown) that extends into gearbox 44through a housing opening 70. This power source gear is placed betweenand meshes with a first input gear 102 keyed to traction drive shaft 58and a second input gear 100 carried on a reel drive shaft 98. Thus,whenever power source 6 is operating, traction drive shaft 58 isrotating, sun gear 60 is rotating, and planetary gears 64 are orbitingaround sun gear 60 such that planetary gear carrier 62 is alsocontinuously rotating.

One end of planetary gear carrier 62 includes a gear 72 that is engagedwith an internal gear formed in the bore of a traction drive clutch drum74. Thus, whenever power source 6 is operating, traction drive clutchdrum 74 normally rotates with traction drive shaft 58, sun gear 60,planetary gears 64 and planetary gear carrier 62. However, when tractiondrive clutch drum 74 is rotating, no power is being supplied to tractiondrum 12.

An internal ring gear 76 is concentrically received around planetarygear carrier 62 and is capable of independent rotation relative toplanetary gear carrier 62 since ring gear 76 is supported on a bushing78 interposed between planetary gear carrier 62 and ring gear 76. Again,when no traction drive is present on traction drum 12 but with powersource 6 operating, planetary gears 64 will crawl around the inside ofring gear 76 as planetary gears 64 are rotated, but ring gear 76 willitself remain stationary.

Ring gear 76 includes a parking brake clutch drum 80 and a tractiondrive gear 82 affixed thereto or made integral therewith. Traction drivegear 82 is connected to the input gear 84 of a generally conventionaldifferential 54. Differential 54 includes first and second output shafts86 l and 86 r which are adapted to independently drive traction drumhalves 12 l and 12 r. Differential 54 can be a Peerless differential,Model No. 100-207.

In order to transmit drive to traction drum 12, a traction band brake 88is located around traction drive clutch drum 74. Normally, traction bandbrake 88 is in a loosened state. However, when various controls onhandle assembly 8 are manipulated, as will be described hereafter,traction band brake 88 can be tightened around traction drive clutchdrum 74 by rotating a lever arm 90, to which the ends of traction bandbrake 88 are connected as illustrated at 92. This rotating action oflever arm 90 moves one end of traction band brake 88 relative to theother end of traction band brake 88 to tighten traction band brake 88around traction drive clutch drum 74.

When traction band brake 88 is so tightened, rotation of traction driveclutch drum 74 and of planetary gear carrier 62 is stopped. However,traction drive shaft 58, sun gear 60, and planetary gears 64 are allstill rotating. The rotation of planetary gears 64 is now transmitted toring gear 76 to rotate ring gear 76 and hence rotate traction drive gear82 that is fixed to ring gear 76. This, in turn, transmits the drivethrough differential 54 to the output shafts 86 l and 86 r ofdifferential 54.

The outer end of each differential output shaft 86 l and 86 r is locatedoutside gearbox 44 where it is connected by an enclosed belt or chaindrive 90 l and 90 r to one of the shafts 14 l and 14 r for one oftraction drum halves 12 l and 12 r. Thus, whenever traction band brake88 is selectively tightened by the operator while power source 6 of walkreel mower 2 is operating, drive from power source 6 will be transmittedthrough the drive reduction provided by the planetary gearing and ringgear, through differential 54, and through the individual belt or chaindrives 90 l and 90 r to the shafts 14 l and 14 r of traction drum halves12 l and 12 r.

Much of the drive reduction needed for traction drum halves 12 l and 12r is accomplished by the reduction provided within gearbox 44 itself.However, some reduction also occurs within the belt or chain drives 90 land 90 r which connect the differential output shafts with the shaftsfor traction drum halves 12 l and 12 r. This reduction within the beltor chain drives 90 l and 90 r is provided by sizing the input and outputpulleys or sprockets differently from one another to further reduce thespeed of the differential output shafts. However, if so desired, aplanetary gear drive could be provided within gearbox 44 having multipleplanetary stages such that the planetary gear drive itself providessubstantially all of the desired drive reduction.

A parking brake 56 for walk reel mower 2 is conveniently and simplyformed by the parking brake clutch drum 80 fixed to or formed with ringgear 76 along with a second, parking band brake 94 included withingearbox 44. Parking band brake 94 can be tightened in much the samemanner as traction band brake 88, i.e. by pivoting a lever arm 96 topull one end of the band brake relative to the other end of the bandbrake in a direction that tightens the band brake around the clutchdrum. This is done by any suitable operational control provided on walkreel mower 2 and any suitable linkage for providing rotation of leverarm 96.

When the parking brake control is actuated and parking band brake 94 istightened, parking band brake 94 grips parking brake clutch drum 80secured to ring gear 76 with sufficient force to hold ring gear 76against rotation caused by walk reel mower 2 rolling down a typicalincline found on a golf course or the like. This gripping force ischosen to hold walk reel mower 2 in place assuming traction drive 46 isnot operating. If traction drive 46 is operating, parking band brake 94will not provide sufficient force to hold ring gear 76 as the forceprovided by parking band brake 94 will be overpowered by the force oftraction drive 46 on ring gear 76. However, parking brake 56 is onlyintended to be used when traction drive 46 is disengaged and no tractionforce is being transmitted to ring gear 76. In this case, the grippingforce provided by parking band brake 94 is sufficient to hold ring gear76 against any rotation which might be induced by walk reel mower 2rolling down an incline, thus keeping walk reel mower 2 stationaryagainst unintended movement.

The same gearbox 44 which provides a traction drive 46 for traction drum12 and a parking brake 56 for walk reel mower 2 also provides a reeldrive 48 for cutting reel 22. This reel drive 48 will now be described,again with reference to the exploded perspective view of FIG. 11.

A reel drive shaft 98 is rotatably journalled in gearbox 44 and isparallel to traction drive shaft 58. Reel drive shaft 98 includes aninput gear 100 which is continuously rotated whenever power source 6 isoperating. This input gear 100 is continuously rotated by the same powersource gear (not shown) that is driven by the engine, this power sourcegear mating with and driving both input gears 100 and 102. Thus, whenpower source 6 is operating and the power source gear (not shown)contained in gearbox 44 is rotating, the engagement between this powersource gear and input gear 100 on reel drive shaft 98 causes input gear100 on reel drive shaft 98 to be continuously rotated.

Input gear 100 on reel drive shaft 98 does not continuously rotate reeldrive shaft 98 as it is supported on reel drive shaft 98 by a bearing104. Thus, input gear 100 on reel drive shaft 98 can rotate while reeldrive shaft 98 is stationary. The operator can selectively place reeldrive shaft 98 into operation by operating a control on walk reel mower2, which control will be described in more detail hereafter, to slide acone clutch 106 into engagement with input gear 100 on reel drive shaft98. Cone clutch 106 is slidably, but non-rotatably affixed, to reeldrive shaft 98. Thus, when cone clutch 106 is slid along reel driveshaft 98 and into engagement with input gear 100, cone clutch 106 willtransmit the drive from input gear 100 to reel drive shaft 98 to beginrotating reel drive shaft 98. Reel drive shaft 98 includes an outputgear 108 on the other end thereof from which the drive for cutting reel22 may be taken. This output gear 108 is not shown in FIG. 11, but isshown in FIGS. 12 and 13.

The integrated gearbox 44 disclosed herein has many advantages. Itconveniently locates both the traction and reel drives 46 and 48 withina single gearbox. This avoids the cluttered look of prior art walk reelmowers many of which use separate gearboxes for these drives. It alsolocates the clutches 88 and 106 for controlling or actuating thetraction and reel drives 46 and 48 within a single gearbox. Sincegearbox 44 can be lubricated with oil, both the traction and reel drives46 and 48 will be kept lubricated together, without having to keepseparate gearboxes lubricated.

In addition, considering just traction drive 46 alone, the singlegearbox 44 houses both a planetary gear reduction drive as well asdifferential 54. This avoids having to place differential 54 in tractiondrum 12 itself, as in older walk reel mower designs. In addition, theclutch 88 for initiating traction drive 46 is a simple band brake whichis tightened around traction drive clutch drum 74 to cause the drive ofplanetary gears 64 to be transmitted up through ring gear 76 rather thanto planetary gear carrier 62. Thus, traction drive 46 is compact, simpleand durable. Accordingly, traction drive is transmitted to traction drum12 in a highly efficient and easy to operate manner.

Moreover, as previously described, a parking brake 56 is easilyincorporated into the unit by forming another clutch drum 80 with ringgear 76 and using a second band brake 94 to grip this clutch drum.Again, this is a compact, simple and durable structure.

The Flexible, Self-Lubricating Drive Shaft Driving Cutting Reel 22

The output gear 108 located on reel drive shaft 98 is coupled to cuttingreel 22 through a first belt or chain drive 110 that extends downwardlyfrom gearbox 44 to a point above reel cutting unit 18. This first beltor chain drive 110 is preferably arranged to provide a 1 to 1 drive, butother than a 1 to 1 drive could be used. This first belt or chain drive110 is located generally over reel cutting unit 18 due to the locationof gearbox 44. Thus, it is necessary to transfer drive from the lowerend of first belt or chain drive 110 over to one side of reel cuttingunit 18 and then down to the shaft of cutting reel 22. The drive must betransferred and kept in proper operation even though reel cutting unit18 can float or move relative to reel mower frame 4 through motion withrespect to two axes, i.e. the x and y axes described above.

Referring now to FIG. 6, the drive is transferred from the first belt orchain drive 110 that extends downwardly from gearbox 44 by atransversely extending drive shaft 112 arranged above reel cutting unit18. Drive shaft 112 comprises flexible joints 114 at either end, in thenature of universal couplings, which are formed from a solid piece ofstainless steel material having a spiral slot or groove formed therein.Similar joints are commercially available from Helical Products of SantaMaria, Calif. The joints are referred to by Helical Products as flexiblehelix beam couplers.

A stub shaft 116 is secured to each joint and extends inwardly so thatstub shafts 116 on the opposed joints 114 point towards one another, notaway from one another. Each stub shaft 116 has a non-circularcross-sectional configuration. In other words, each stub shaft 116 hasan outer periphery in the form of a square or hex shape or the like.Each stub shaft 116 is received within the interior bore 118 of anintermediate coupler 120. Bore 118 of intermediate coupler 120 is shapedto mate with the cross-sectional configuration of stub shafts 116. Thus,if stub shafts 116 have a hex head configuration, bore 18 will have ahex head configuration as well.

As should be apparent, each stub shaft 116 is slidably received withinintermediate coupler 120 so that stub shafts 116 can move in and outrelative to intermediate coupler 120 as reel cutting unit 18 rolls aboutthe x axis. Stub shafts 116 and intermediate coupler 120 are designed sothat stub shafts 116 never come out of intermediate coupler 120 as reelcutting unit 18 rolls during operation of walk reel mower 2 as thiswould disrupt the drive provided by drive shaft 112. Stub shafts 116 aremerely able to slide back and forth within intermediate coupler 120 toaccommodate the maximum permissible amount of rolling motion withoutever disengaging intermediate coupler 120. As intermediate coupler 120and stub shaft 116 nearest the first belt or chain drive 110 fromgearbox 44 rotate, this rotation will be transmitted throughintermediate coupler 120 to stub shaft 116 adjacent the left side ofreel cutting unit 18. From that point, the drive can be transferred tothe shaft of cutting reel 22 by a second 1 to 1 belt or chain drive 122.See FIG. 5.

Desirably, joints 114 as well as intermediate coupler 120 are made frommaterials which do not require external lubrication. For example,coupler 120 is made from a nylon material impregnated with a non-oilbased lubricant, such as molybdenum disulfide. This material provide itsown lubrication without requiring the material to be immersed or bathedwith oil. Using such self-lubricating materials in drive shaft 112 is anadvantage in a walk reel mower as there is no possibility of an oil leakthat might damage the grass. Thus, drive shaft 112 disclosed herein isan efficient and environmentally friendly structure for driving cuttingreel 22 from gearbox 44, even though reel cutting unit 18 can itselfpitch and roll relative to gearbox 44.

Drive shaft 112 could also be used on reel mowers carried on or formedas part of riding mowers.

The Operational Controls

Another aspect of this invention relates to the operational controls forwalk reel mower 2. Referring to FIG. 14, a first pivotal control handle124 is carried on handle assembly 8 of walk reel mower 2 on one of thehandle tubes. This first control handle 124 actuates parking brake 56.When first control handle 124 is pivoted from one position to another, acontrol linkage is pulled which causes the rotation of lever arm 96 forparking band brake 94. This causes parking band brake 94 to tighten onparking brake clutch drum 80 to prevent ring gear 76 from turning duringnon-powered, inadvertent movement of walk reel mower 2, such as whenwalk reel mower 2 might roll down an incline. Movement of first controlhandle 124 back to its normal position will loosen parking band brake 94and release parking brake 56.

Normally, when first control handle 124 is pivoted downwardly andforwardly relative to handle assembly 8, parking brake 56 is notactuated. When first control handle 124 is pivoted rearwardly andupwardly relative to handle assembly 8, parking brake 56 is actuated.The position of first control handle 124 in FIG. 14 illustrates theposition in which parking brake 56 is actuated.

A single, second control handle 126 is provided for operating bothtraction drive 46 and cutting reel 22. This is particularly advantageousand an improvement over prior art walk reel mowers. Second controlhandle 126 is shown in detail in FIGS. 15 and 16.

A control housing 128 is secured to that handle tube which does notmount first control handle 124. A semicircular sleeve 130 is providedfor being received around the handle tube for attaching control housing128 to the handle tube. A substantially horizontal, fixed pivot pin 132extends through one side wall of control housing 128 and is received inan aligned bore 133 in an intermediate wall in control housing 128. Thispivot pin 132 serves as a fixed pivot axis for second control handle126.

Second control handle 126 is pivotally mounted on fixed pivot pin 132 soas to rotate around fixed pivot pin 132. The lower end of second controlhandle 126 has a yoke 134. As shown in FIG. 16, yoke 134 has spaced legs136 which have openings 138 for journalling second control handle 126 onfixed pivot pin 132. Yoke 134 includes a radially extending arm 140 thatis attached to one end of a spring 142. The other end of spring 142 isattached to a cable or linkage 144 which actuates lever arm 90 ontraction band brake 88 to actuate traction drive 46.

Pivoting second control handle 126 downwardly about the pivot axisformed by fixed pivot pin 132, i.e. in the direction of the arrow C inFIG. 14, pulls upwardly through spring 142 on cable 144 that actuateslever arm 90 on traction band brake 88. This causes traction band brake88 to be tightened. Tightening traction band brake 88 stops or locks upplanetary gear carrier 62. In turn, this allows planetary gears 64 torotate ring gear 76. Thus, rotating second control handle 126 downwardlyand forwardly places walk reel mower 2 into movement by actuatingtraction drive 46. Second control handle 126 is shown in FIG. 14 in aposition in which traction drive 46 is engaged.

Second control handle 126 further includes a selectively operable togglemember 146 on the top thereof for actuating cutting reel 22. When togglemember 146 is located coaxially in line with second control handle 126,cutting reel 22 is stationary. However, if the user first toggles thetoggle member 146 to one side of second control handle 126, so thattoggle member 146 is now inclined relative to the axis of second controlhandle 126, cutting reel 22 will be placed in operation when secondcontrol handle 126 is pivoted in a direction that also engages tractiondrive 46.

A reciprocal rod 148 is located inside second control handle 126 whichrod 148 is moved up and down relative to second control handle 126 whentoggle member 146 is toggled. The bottom of toggle member 146 ispivotally mounted to second control handle 126 by a toggle base 150 thatrotates about a transversely offset pivot pin 152. Toggle base 150 isalso pinned at 154 to the top of reciprocal rod 148. When toggle member146 is coaxially aligned with second control handle 126, the pinnedconnection 154 to reciprocal rod 148 is raised above the offset pivotpin 152, thereby drawing reciprocal rod 148 upwardly relative to secondcontrol handle 126. When toggle member 146 is toggled to one siderelative to second control handle 126 as shown in FIGS. 14-16, so thatthe co-axial relationship between toggle member 146 and second controlhandle 126 is no longer present, the pinned connection 154 to reciprocalrod 148 is now lowered relative to the offset pivot pin 152 to be atabout the same level as the offset pivot pin 152, thereby pushingreciprocal rod 148 downwardly relative to second control handle 126.

A pivotal coupling link 156 is pivotally mounted on fixed pivot pin 132in control housing 128 between the spaced legs 136 of yoke 134 in aposition underlying the lower end of second control handle 126. Thispivotal coupling link 156 includes a notch 158 in one side that is sizedto receive the lower end of reciprocal rod 148 in second control handle126. Pivotal coupling link 156 is independently rotatable relative tosecond control handle 126, i.e. pivotal coupling link 156 does notnecessarily rotate with second control handle 126 when second controlhandle 126 rotates. It only rotates with second control handle 126 whenthe lower end of reciprocal rod 148 in second control handle 126 islowered into notch 158 on pivotal coupling link 156.

Pivotal coupling link 156 is further secured to one end of a spring 160.The other end of this spring 160 is attached to a cable or linkage 162which actuates cone clutch 106 on reel drive shaft 98 to actuate cuttingreel 22. Pulling upwardly on this cable 162 rotates a bell crank linkage164 on top of gearbox 44, which bell crank linkage 164 is connected insome fashion to cone clutch 106, to slide cone clutch 106 back and forthon reel drive shaft 98.

When toggle member 146 is toggled to the side as shown in FIGS. 14-16,reciprocal rod 148 is moved down such that the lower end of reciprocalrod 148 enters into notch 158 in coupling link 156. When the lower endof reciprocal rod 148 enters into notch 158, coupling link 156 is nowcoupled to second control handle 126 for joint rotation therewith. Thus,rotating second control handle 126 to actuate traction drive 46 willalso cause cutting reel 22 to be placed into operation. If the operatordoes not toggle the toggle member 146 to the side before rotating secondcontrol handle 126, such that reciprocal rod 148 remains in a raisedposition relative to second control handle 126 with the lower end ofreciprocal rod 148 being out of engagement with notch 158 in couplinglink 156, then only traction drive 46 is engaged, with cutting reel 22remaining stationary.

The integrated traction drive/cutting reel control handle 126 isadvantageous over prior art walk reel mowers in which two separatecontrol handles are sometimes provided or in which the cutting reelcontrol handle is located down on reel mower frame 4. In this lattersituation, the operator must walk around from behind handle assembly 8to actuate and deactuate cutting reel 22. This can be onerous andtime-consuming to do. With the single second control handle 126disclosed herein, the operator can separately engage and disengagecutting reel 22 from behind handle assembly 8 without leaving the normaloperating position.

The advantages in this are best explained in reference to the use of awalk reel mower of this type in cutting golf greens or the like. Whencutting a number of such greens, the operator will first cut one green.Following the cutting of one green, the operator will the drive walkreel mower 2 to the next green. When making the trip to the next green,it is desirable that cutting reel 22 be disengaged and only tractiondrive 46 be engaged.

However, as a practical manner, many operators do not disengage cuttingreel 22 during such a trip because they have to leave the operator'sposition to reach the control handle or lever which controls cuttingreel 22, such control handle or lever normally being present on reelmower frame 4 in front of handle assembly 8. To disengage cutting reel22, the operator first has to disengage traction drive 46, walk aroundin front of handle assembly 8 to disengage cutting reel 22, then walkback behind handle assembly 8 to re-engage traction drive 46 to allowwalk reel mower 2 to be driven to the next green. When the next green isreached, this procedure has to be repeated. Namely, to now engagecutting reel 22, the operator again has to disengage traction drive 46,walk around in front of handle assembly 8 to now re-engage cutting reel22, and then walk back behind handle assembly 8 to re-engage tractiondrive 46.

This procedure is so onerous and bothersome to many operators that suchoperators simply don't take the time to disengage cutting reel 22 whendriving walk reel mower 2 from one location to another. Instead, theysimply let cutting reel 22 remain powered and tip walk reel mower 2 backon its traction drum 12 to keep reel cutting unit 18 raised duringtransport. This is disadvantageous as additional wear and tear is placedon reel cutting unit 18 because it is operating at times when it neednot. In addition, it is tiring to the operator to keep reel cutting unit18 elevated off the ground during transport.

By contrast, the single control handle 126 of this invention allows theoperator to disengage cutting reel 22 with the flick of a wrist and onthe fly while traction drive 46 remains engaged. All the operator needsto do is to toggle the toggle member 146 back to its upright, in lineposition with second control handle 126 and reciprocal rod 148 willleave notch 158 in coupling link 156. The spring 160 will then causecoupling link 156 to return to its unactuated position and the actuatingcable 162 will return to its position in which cone clutch 106 isdisengaged. However, traction drive 46 remains engaged. Thus, at the endof one mowing operation, walk reel mower 2 of this invention can beeasily driven to another location with cutting reel 22 being disengagedsimply by flicking toggle member 146 to its upright position.

When a new mowing location is reached, the operator must disengagetraction drive 46 before re-engaging cutting reel 22. But, with thesecond control handle 126 disclosed herein, this is easily done simplyby rotating second control handle 126 rearwardly and upwardly on handleassembly 8 to its normal unactuated position. Then, both traction drive46 and cutting reel can be easily re-engaged by first toggling thetoggle member 146 to one side to push reciprocal rod 148 into notch 158in coupling link 156 and by then pivoting second control handle 126downwardly and forwardly in the slot in which second control handle 126is received. This can be done quickly and while the operator stays inthe normal operational position in back of handle assembly 8.

If desired, a pivotal throttle 166 can be pivotally supported on anotherpivot pin 168 carried on the same control housing 128 that mounts secondcontrol handle 126. This throttle 166 is connected by an actuating cable170 to the throttle on power source 6 to allow the operator to increaseor decrease the power provided by power source 6. Placing throttle 166on this control housing so that throttle 166 is adjacent second controlhandle 126 groups all the controls together that relate to the actuationand control of the powered components on walk reel mower 2.

Obviously, the actuated/not actuated positions of the first and secondcontrol handles 124 and 126 could be reversed if so desired.

The Basket Mounting

In many prior art walk reel mowers of this type, the grass basket 172 iscarried on reel mower frame 4 by upwardly and forwardly inclinedcylindrical pins provided at two, transversely spaced locations on thefront of reel mower frame 4. The grass basket includes a rearwardly anddownwardly inclined seating groove on each side thereof for receivingone of these pins. The operator can pull the grass basket off reel mowerframe 4 by pulling up and forwardly on the grass basket to remove theseating grooves from the pins.

One difficulty with this known seating groove/pin arrangement is thatcertain manipulation of walk reel mower 2 can cause the pins toinadvertently disengage the grooves. For example, this sometimes happenswhen the operator lifts upwardly on the rear of the reel mower. If theoperator lifts high enough, and if the front of the grass basket isloaded with grass clippings, the pins can be forced out of the groovesand the grass basket will become disengaged. This forces the operator towalk around and reconnect the grass basket to reel mower frame 4.

To avoid this problem, the Applicants' disclose herein two transverselyspaced sockets 174 on reel mower frame 4 for receiving seating pins 182on grass basket 172. This subject matter is most clearly shown in FIGS.17-19.

Each socket 174 is attached to the front of reel mower frame 4 generallyoverlying reel cutting unit 18. Each socket 174 is shaped as an upwardlyfacing trough 176 having spaced side walls 178 connected to each otherat the bottom. For example, trough 176 could have a channel shape withvertical side walls and a flat bottom, a V-shape, a U-shape, etc. Trough176 of each socket 174 is open at the front but is closed at the rear bya top wall 180. Thus, socket 174 has an upwardly open front portion andan upwardly closed rear portion. In addition, trough 176 of each socket174 is upwardly inclined as it extends forwardly. See FIG. 19.

The grass basket 172 has two rearwardly extending seating pins 182 eachhaving a downwardly inclined distal leg 184. When grass basket 172 isflat and level, the angle of inclination of distal leg 184 matches theangle of inclination of socket 174 allowing distal leg 184 to beinserted into socket 174 with leg 184 then being received in socket 174.Each leg 184 fits down into one socket 174 with leg 184 being longenough to fit down into the upwardly closed rear portion of socket 174beneath top wall 180. However, the front portion of each socket 174 isopen at the top and is not similarly constricted by a top wall 180.

When the operator lifts up on the rear of walk reel mower 2, the frontof walk reel mower 2 pivots downwardly about traction drum 12 so thatsockets 174 begin pivoting downwardly as well. This downward pivotingmotion of sockets 174 effectively causes grass basket 172 to engage theground which, in turn, causes distal legs 184 of pins 182 to pivotupwardly relative to sockets 174, i.e. distal legs 184 will actuallypivot upwardly at least partially through the upwardly open frontportion of sockets 174. However, since the front portion of sockets 174is upwardly open and is not enclosed by a top wall, there is no cammingforce exerted on distal legs 184 by sockets 174 that is sufficient tocam pins 182 out of sockets 174. This avoids inadvertently disengaginggrass basket 172 from reel mower frame 4. Accordingly, grass basket 172will more easily stay seated on reel mower frame 4 with the socket174/seating pin 182 configuration shown herein than with prior artconfigurations, even when grass basket 172 is loaded with grassclippings.

The Bedknife Mounting

Referring now to FIG. 20, bedknife 24 is typically mounted to the bottomof a triangular bedbar 186 that is itself attached to pivotal supportarms 188 at either side of reel cutting unit 18. Support arms 188 pivotabout a pivot axis identified as 190. Bedknife adjusters 32 work, in aknown manner, by pivoting support arms 188 about pivot axis 190 in thedirection of arrows C in FIG. 20.

As cutting reel 22 wears, the outside diameter of reel 22 shrinks andthe distance between bedknife 24 and the outside diameter of reel 22grows. When this distance becomes too large, the quality of cut isadversely affected. Thus, it is periodically necessary to rotatebedknife 24 in a direction (i.e. a counter-clockwise direction in FIG.20) which moves bedknife 24 upwardly towards reel 22 to compensate forwear on reel 22. Again, this is the basic purpose of bedknife adjusters32 and the use of such adjusters for this type of adjustment is wellknown in the art.

In prior art reel mowers of this type having a pivotal bedknife whichpivots towards the cutting reel to compensate or adjust for reel wear,the bedbar/bedknife combination would typically pivot about a pivot axislocated generally at the rear of bedbar 186. This prior art pivot axisis shown in FIG. 20 as 192. The Applicants have discovered that theplacement of prior art pivot axis 192 and the geometry of bedbar 186relative to reel 22 causes the front edge of bedknife 24 to also moverearwardly relative to reel 22 as it moves upwardly. Thus, in prior artreel mowers, as the bedknife was progressively pivoted up to compensatefor wear in the cutting reel, the line of contact between the bedknifeand the cutting reel would progressively shift rearwardly. As thishappens, the Applicants further discovered that the cutting reel wouldbecome more aggressive in its cutting action and the quality of the cutwould change.

In reel mowers of this type, particularly those used for cutting greenson golf courses to very low height of cuts, it is important that thequality of cut remain consistent and not change over time. As just notedabove, the quality of cut does change in prior art mowers when thebedknife is pivoted up towards the cutting reel to compensate for wear.

This invention relates to a new location 190 for the pivot axis for thebedbar 186/bedknife 24 combination that is raised and slightly to therear of the usual location 192 for this pivot axis. This new locationhas been selected, in conjunction with the geometry of the bedbar186/bedknife 24 combination in relation to cutting reel 22, so that therearward shifting of the line of contact between bedknife 24 and reel 22does NOT occur. In other words, in a reel mower according to thisinvention, as bedknife 24 pivots about pivot axis 190, the new location190 for the pivot axis of bedknife 24 ensures that the front edge ofbedknife 24 now stays in approximately the same longitudinal location(within about 0.005 inches) relative to cutting reel 22 as the frontedge of bedknife 24 rises. This ensures that the quality of cut remainsmuch more consistent even as bedknife 24 is adjusted to compensate forreel wear.

Bedknife 24 has been shown as a separate component on the bottom ofbedbar 186 to allow ease of removal of bedknife 24 for sharpening orreplacement. However, bedbar 186 and bedknife 24 could be integrallyformed with one another or bedknife 24 could be supported in some otherfashion for pivoting motion on reel cutting unit 18. The pivotalbedknife mounting disclosed herein could also be used on reel mowerscarried on or formed as part of riding mowers.

The Back Plate of the Reel Cutting Unit

Referring now to FIG. 21, an improved back plate for a reel cutting unitis shown generally as 200. The back plate has an upper portion 202 and alower lip 204 protruding forwardly and downwardly from upper portion202. Upper portion 202 has a closed, tubular cross-sectionalconfiguration in the form of a hollow beam to provide strength. Lowerlip 204 is solid, rather than being hollow, and is relatively thincompared to the thickness of upper portion 202.

Preferably, back plate 200 can be extruded in one piece out of aluminum.Thus, back plate 200 is light, but yet strong because of the hollow beamconfiguration of upper portion 202. Back plate 200 can be madesufficiently strong so that it alone will provide sufficient strength tounite side plates 20 without having the usual additional cross-membersor stringers that normally are secured at each end to side plates 20 toprovide strength. Back plate 200 as disclosed herein can be used on reelcutting units for walk reel mowers or for riding mowers.

Various other modifications of this invention will be apparent to thoseskilled in the art. Accordingly, the invention is to be limited only bythe appended claims.

1. A reel cutting unit for a reel mower, which comprises: (a) a reelcutting unit frame comprising spaced side plates connected to an arcuateback plate, wherein the reel cutting unit frame is self supporting forrolling over the ground by front and rear rollers extending between theside plates with the front and rear rollers allowing the reel cuttingunit frame to adapt to changes in ground contour by pivoting the reelcutting unit frame about both a transverse roll axis and a longitudinalroll axis relative to remaining portions of the reel mower on which thereel cutting unit is carried, wherein each of the front and rear rollershas an axis of rotation relative to the side plates, and wherein theaxis of rotation of the front roller is vertically movable up and downrelative to each side plate by a height of cut adjustment mechanismcarried on the reel cutting unit frame; (b) a helically bladed cuttingreel rotatably journalled between the side plates and positioned infront of the back plate and between the front and rear rollers; (c) abedknife extending between the side plates along the length of cuttingreel for cooperating with the cutting reel to cut grass, the bedknifebeing pivotally adjustable about a pivot axis relative to the sideplates to compensate for wear in the cutting reel, wherein the pivotaxis of the bedknife is located longitudinally between an axis ofrotation of the cutting reel and the axis of rotation of the rearroller; and (d) wherein the pivot axis of the bedknife is locatedvertically above the axis of rotation of the rear roller in a locationthat is chosen such that the front edge of the bedknife stays withinabout 0.005 inches of the same longitudinal location relative to thecutting reel as the front edge of the bedknife rises upwardly tocompensate for wear in the cutting reel.